1. Field of the Invention
The present invention relates to a lamp unit, a projector and a fixing method of a light source lamp and a reflector. More specifically, it relates to a lamp unit including a light source lamp and a reflector for reflecting light beam from the light source lamp, a projector having the lamp unit and a fixing method of the light source lamp and the reflector.
2. Description of Related Art
Conventionally, a projector has been used: for presentation at conference, scientific society and exhibition. Such projector modulates a light beam irradiated by a lamp unit in accordance with image information to form an optical image and to enlarge and project the optical image.
The lamp unit includes a light source lamp having a light emitting portion for irradiating the light beam, and a substantially conic (cup-shaped) reflector for reflecting the light beam from the light emitting portion. The light source lamp is directly fixed at the bottom of the reflector by cement etc. with the light emitting portion being disposed at substantially the same position as the focus of the reflector so that the light emitting portion and neighborhood thereof are accommodated in the reflector.
However, since an attachment for attaching and fixing the light source lamp has to be formed at the bottom of the above-described lamp unit, the configuration of the reflector becomes complicated and accuracy of the reflection surface is difficult to be improved.
Further, since the attachment is formed on the reflector as an optical component, considering the accuracy of the reflection surface of the reflector etc., it is difficult for the so attachment to have the most appropriate shape for holding and fixing the light source lamp, i.e. a complicated shape, so that the light source lamp may not be sufficiently held.
An object of the present invention is to provide a lamp unit, a projector and a fixing method of light source lamp and reflector capable of improving accuracy of the reflector and capable of sufficiently holding the light source lamp.
In order to attain the above object, a lamp unit according to an aspect of the present invention includes following arrangement.
A lamp unit according to the present invention includes: a light source lamp having a light emitting portion; a reflector disposed with the light emitting portion and a fixing portion thereinside that reflects a light beam irradiated by the light emitting portion; and a fixing member to which fixes the fixing portion of the light source lamp and the reflector are fixed; the light source lamp and the reflector being respectively fixed to the fixing member in a mutually independent manner, and a portion of the light source lamp between the fixing portion and the light emitting portion being exposed to an outside of the reflector.
The fixing member may be formed as an integrated member or, alternatively, may be divided in plural.
Since the light source lamp and the reflector are respectively independently fixed to the fixing member in the present invention, the attachment for attaching and fixing the light source lamp is not necessary to be formed on the reflector as an optical component. Accordingly, the shape of the reflector can be simplified and the accuracy of the reflection surface thereof can be easily improved, thereby enhancing illumination of the lamp unit.
Since the light source lamp is attached to the fixing member, unlike the conventional arrangement where the shape of the attachment has to be determined considering accuracy of the reflector etc., the attachment structure (a structure corresponding to the attachment of the conventional reflector) having the most suitable shape for supporting and fixing the light source lamp can be easily formed on the fixing member, thereby sufficiently supporting the light source lamp.
Since the portion between the light emitting portion and the fixing portion of the light source lamp, in other words, the portion disposed adjacent to the light emitting portion and of which temperature is easily raised in lighting the light source lamp, is exposed to the outside of the reflector, thereby allowing the heat to escape from the portion. Accordingly, the portion can be easily cooled, so that the temperature of the light emitting portion can be prevented from becoming too high, thereby lengthening the life of the light source lamp.
Incidentally, since the light emitting portion and the neighborhood of the light emitting portion of the light source lamp are conventionally accommodated in the reflector, the temperature of the light source lamp is likely to become high when the lamp is lit and the light source lamp""s life is likely to be shortened
On the other hand, since the light source lamp is fixed to the fixing member in the present invention, the portion remote from the light emitting portion (fixing portion) can be supported and fixed and the portion between the light emitting portion and the fixing portion can be exposed to the outside of the reflector.
In the lamp unit according to the present invention, a protective light transmitting member may preferably be provided on a light-emitting side of the reflector.
Since the light-emitting side of the reflector is covered with the light transmitting member, even when the light source lamp is exploded, the fragment can be prevented from scattering to the outside of the reflector.
The light transmitting member of the lamp unit according to the present invention may preferably be divided in plural parts.
Since the light transmitting member is divided in plural, i.e. composed of, for instance, a plurality of small glass plates, when the temperature inside the reflector is raised in accordance with temperature increase of the light source lamp in lighting, the crack of the light transmitting member on account of thermal deformation and the crack of the light transmitting member caused by fissure generated in processing the insert hole on the light transmitting member can be prevented.
In the lamp unit of the present invention, the light transmitting member may preferably be fixed to the fixing member.
Since the light transmitting member is fixed to the fixing member, the attachment process thereof can be facilitated as compared to an arrangement attaching the light transmitting member to the reflector.
Especially, since a troublesome process for attaching, for instance, adjacently-located small glass plates one by one is accompanied when the separate type light transmitting member is used, workability of the process can be improved by attaching the light transmitting member to the fixing member.
In the lamp unit according to the present invention, the fixing member may preferably comprise a holder to which the fixing portion of the light source lamp is fixed and held and an air circulation channel may preferably penetrate the holder
Since an air circulation channel is provided to the holder of the fixing member, the fixing portion of the light source lamp fixed and held by the holder can be efficiently cooled, thereby lengthening the life of the light source lamp.
Since the air circulation channel is formed on the holder of the fixing member, the shape of the reflector can be prevented from being too complicated and the air circulation channel can be easily formed.
On the other hand, in order to attain an object of the present invention, a projector according to another aspect of the present invention is characterized in having the above lamp unit.
According to the present aspect of the present invention, the above lamp unit is attached to the projector, thereby obtaining the same effects and advantages as the above.
In order to attain an object of the present invention, a fixing method of light source lamp and reflector and assembling method of lamp unit according to still another aspect of the present invention is conducted according to following steps.
A fixing method of a light source lamp and a reflector according to the above aspect of the present invention includes the steps of: fixing one of the light source lamp and the reflector to a fixing member; positioning the other one of the light source lamp and the reflector relative to the one of the light source lamp and the reflector; and fixing the other one of the light source lamp and the reflector to the fixing member in a mutually independent manner.
An assembling method of a lamp unit including a light source lamp that irradiates light beam and a reflector that reflects the light beam from the light source lamp is characterized in including the steps of: fixing one of the light source lamp and the reflector to a fixing member; positioning the other one of the light source lamp and the reflector relative to the one of the light source lamp and the reflector; and fixing the other one of the light source lamp and the reflector to the fixing member in a mutually independent manner.
According to the above aspect of the present invention, since the light source lamp and the reflector are respectively independently fixed to the fixing member, the attachment for attaching and fixing the light source lamp as mentioned in the background art section is not necessary to be formed on the reflector as an optical component. Accordingly, the shape of the reflector can be simplified and the accuracy of the reflection surface thereof can be easily improved, thereby enhancing illumination of the lamp unit.
Since the light source lamp is attached to the fixing member, unlike the conventional arrangement where the shape of the attachment has to be determined considering accuracy of the reflector etc., the attachment structure (a structure corresponding to the attachment of the conventional reflector) having the most suitable shape for supporting and fixing the light source lamp can be easily formed on the fixing member, thereby sufficiently supporting the light source lamp.
Further, since the light source lamp and the reflector are respectively positioned relative to the fixing member, positioning freedom of the respective components can be enhanced as compared to the conventional lamp unit having a light source lamp integrally attached with the reflector, thereby facilitating to enhance the illumination of the lamp unit.